Sealable valve bag and method for making a sealable valve bag

ABSTRACT

The valve bag includes a bag body having a valve end portion, the valve end portion constructed to form a filling passage in which a valve sleeve is inserted. The valve sleeve has a first end extending into the interior of the valve bag and a second end extending exteriorily from the bag body. A valve protection member is secured to the second end.

FIELD OF THE INVENTION

[0001] The invention relates generally to sealable valve bags and, morespecifically to the valve sleeve used to fill and seal the valve bags.These shipping sacks are commonly used to contain and transport granularproducts, examples of which are fertilizers, animal feeds or grain.

BACKGROUND OF THE INVENTION

[0002] Flexible bags such as paper shipping sacks may include a sealablevalve sleeve placed in a filling valve, the filling valve is located ina corner of the flexible bag to allow introduction of material that isto be held within the bag. These shipping sacks are commonly used tocontain and transport material such as granular products, examples ofwhich are fertilizers, animal feeds or grain. The sealable sleeveprovides a convenient means to fill and securely close the flexible bagto prevent the contents of the bag from leaking or sifting out of thebag once the bag has been filled. Sleeves may be constructed of avariety of materials such as paper, polyethylene tubing or athermoplastic liner.

[0003] A typical sleeve for a paper shipping sack, such as a pastedvalve type multiwall shipping sack, is made from a rectangular sheet ofkraft paper that is rolled into a cylindrical shape and secured in thecylindrical shape by overlapping or abutting the opposing edges of thesheet of paper to one another and gluing to form a seam. Such a sleeveis described in commonly assigned U.S. Pat. No. 6,164,823, thedisclosure of which is hereby expressly incorporated by reference. Inorder to seal the valve sleeve and therefore the valve passage after theshipping sack is full, heat, typically generated by ultrasonicvibrations, is applied to the exterior surface of the valve sleevemelting the thermoplastic film liner sealing the sleeve and securing thecontents within the shipping sack.

[0004] However, due to the interaction between the vibrating jaw of theultrasonic generator and the outer surface of the valve sleeve, thevalve sleeve is often damaged. The damage to the valve sleeve may makeit possible for the contents of the bag to leak or sift out of the bageven after the sealing operation has been completed.

[0005] Valve sleeves have been constructed of multiple sheets of paperto strengthen the valve sleeve and facilitate filling of the flexiblebag. This design has a high nonconforming rate, often as great asfifteen percent, because the difficulties of aligning the several sheetsof paper to the valve sleeve results in discontinuities around the valvesleeve and allow product to escape from the bag.

BRIEF DESCRIPTION OF THE DRAWINGS

[0006]FIG. 1 is a perspective view of the valve bag, having a valvesleeve constructed in accordance with the invention, with the valvesleeve in the closed position;

[0007]FIG. 2 is a perspective view of the valve bag of FIG. 1, with thevalve sleeve in the open position;

[0008]FIG. 3 is a cross-sectional view of the valve sleeve of FIG. 1,taken along line 1-1 of FIG. 1;

[0009]FIG. 4 is a cross-sectional view of the valve sleeve of FIG. 2,taken along the line 2-2 of FIG. 2 and showing the ultrasonic generatorin contact with the protection member;

[0010]FIG. 5 is a view similar to FIG. 2, showing text or graphics onthe protective member; and

[0011]FIG. 6 is a view similar to FIG. 4, showing the protective memberextending into the valve passage.

DETAILED DESCRIPTION OF THE INVENTION

[0012] A valve sleeve for a flexible bag constructed in accordance withthe present invention includes a cylindrical tube including a heatsealable liner and protective member secured to the cylindrical tube.The protective member is arranged to cover a portion of one end of thevalve sleeve extending from the valve passage protecting the valveduring the sealing process.

[0013] A flexible bag having a valve sleeve constructed to include avalve sleeve in accordance with the invention will be resistant to thedamage caused during sealing of the valve sleeve and prevent contents ofthe flexible bag from escaping due to the damage.

[0014] Further, a flexible bag having a valve sleeve constructed toinclude a protective member in accordance with the invention will beeasier to manufacture and result in less scrap and non-conforming valvebags. The protective member of the present invention is external to thevalve passage to prevent the possibility of discontinuities, and issmaller than the valve sleeve itself to facilitate alignment, both ofthese improvements make the flexible bag easier to manufacture anddecrease the non-conforming rate.

[0015] Additional benefits and features of the invention will beapparent to those skilled in the art from a review of the followingdetailed description taken in conjunction with the drawings and appliedclaims.

[0016] The following description of the disclosed embodiment is notintended to limit the scope of the invention to the precise form orforms detailed herein. Instead, the following description is intended tobe illustrative of the principles of the invention so that others mayfollow its teachings.

[0017] Referring now to the drawings, a valve bag capable of beingsealed is shown in FIGS. 14. A valve bag 10 includes side walls 12, 14,in-folded flap 16, and outer flaps 18, 20. The valve bag 10 ispreferably a valve bag having multiple walls A, B, C adhered together,at least in portion, by layers of adhesive D.

[0018] The valve bag 10, in order to facilitate filling and subsequentsealing also includes a valve sleeve 22. The valve sleeve 22 iscylindrical tube that has a uniform length from its outside end 26, toits inside end 28. The valve sleeve 22 may be formed from a single,rectangular sheet of relatively stiff kraft paper having a thermoplasticfilm 24 that coats the entire interior of the valve sleeve 22, and suchas disclosed and described in the aforementioned U.S. Pat. No.6,164,823. A valve sleeve protection member 34 is affixed to theexterior of the valve sleeve 22, substantially adjacent to the outsideend 26, and extending towards its inside end 28, substantially adjacentwith side wall 12. The entire valve sleeve assembly 36, valve sleeve 22and protection member 34 is affixed in the filling passage 38 createdbetween the in-folded flap 16 and outer flaps 18, 20 and secured byadhesive D.

[0019] The filling of the valve bag 10, is accomplished by inserting afill nozzle (not shown) into the valve sleeve passage 30 defined by thevalve sleeve 22 and discharging material into the interior 32 of valvebag 10. Upon completion of filling, the valve sleeve 22 is typicallysealed by positioning the outside end 26 between a head 40 and an anvil42 of an ultrasonic generator. The protection member 34 is thuspositioned between the head 40 and the valve sleeve 22. Ultrasonicenergy generated by the vibration of the head 40 activates thethermoplastic film 24 to seal the valve sleeve 22. The protection member34 protects the kraft paper surface of the valve sleeve 22 from damagecreated by the motion of the head 40. Accordingly, a tight seal isachieved and damage, such as holes or imperfections, that would allowfilling material to escape the valve bag 10 after sealing was completeis reduced.

[0020] In another embodiment shown in FIG. 5, the valve bag 10 includesa valve sleeve protection member 34 attached to a surface 44 of thevalve sleeve 22. The valve sleeve protection member 34 has been adaptedto display text or graphics 46.

[0021] In another embodiment shown in FIG. 6, the protective member 34is shown to extend into the valve bag filling passage 38. The protectivemember 34 is attached to the lower surface 48 with adhesive D. Theprotective member 34 extends inward towards the interior 32 of the valvebag 10 but is not attached to any of the multiple walls A, B, or C.

[0022] Those skilled in the art will appreciate that, although theteachings of the invention have been illustrated in connection with acertain embodiment, there is no intent to limit the invention to saidembodiment. On the contrary, the intention of this application is tocover all modifications and embodiments fairly falling within the scopeof the appended claims either literally or under the doctrine ofequivalents.

What is claimed is:
 1. A valve bag apparatus for the containment ofmaterial, comprising: a bag body portion having a valve end portion; afilling passage formed in the bag body at the valve end portion; asealable valve sleeve secured within the filling passage, the sealablevalve sleeve having a first end extending into the interior of the bagbody and a second end extending exteriorily from the bag body; and aprotection member secured to the second end.
 2. The valve bag of claim1, wherein the protection member extends inward to a positionsubstantially adjacent to the exterior of the bag body.
 3. The valve bagof claim 1, wherein the protection member comprises a piece of paper. 4.The valve bag of claim 1, wherein the protection member comprises aself-adhesive label.
 5. The valve bag of claim 4, wherein the protectionmember contains text or graphics.
 6. The valve sleeve of claim 1,wherein the protection member is disposed on the head side of theultrasonic generator.
 7. The valve sleeve of claim 1, wherein theprotection member extends into the filling passage.
 8. The valve bag ofclaim 1, wherein the valve sleeve has a first surface and a secondsurface and the protective member engages both surfaces.
 9. A valve bagapparatus for the containment of material, comprising: a bag bodyportion having a valve end portion; at least one in-folded flap memberand at least one out-folded flap member disposed in the valve endportion to form a filling passage; a sheet secured to the fillingpassage having a first end extending inwardly to a position within thebag body and a second end extending exteriorily from the bag body, thesheet having a first edge and a second edge disposed substantiallyadjacent to each other to define an interior surface and an exteriorsurface; a heat sealable material coating the interior surface; and aprotective member secured to the second end.
 10. A method ofconstructing a valve bag, the method comprising the steps of: providinga bag body portion having a valve end portion; constructing a fillingpassage in the bag body at the valve end portion; securing a valvesleeve within the filling passage, the valve sleeve having a first endextending into the bag body and a second end extending exteriorily fromthe bag body; and securing a protective member to the second end.